package main import ( "bytes" "fmt" "mime/multipart" "net/http" "strconv" "github.com/disintegration/imaging" "github.com/gofrs/uuid" "github.com/knadh/listmonk/internal/media" "github.com/labstack/echo" ) const ( thumbPrefix = "thumb_" thumbnailSize = 90 ) // imageMimes is the list of image types allowed to be uploaded. var imageMimes = []string{ "image/jpg", "image/jpeg", "image/png", "image/svg", "image/gif"} // handleUploadMedia handles media file uploads. func handleUploadMedia(c echo.Context) error { var ( app = c.Get("app").(*App) cleanUp = false ) file, err := c.FormFile("file") if err != nil { return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Invalid file uploaded: %v", err)) } // Validate MIME type with the list of allowed types. var typ = file.Header.Get("Content-type") if ok := validateMIME(typ, imageMimes); !ok { return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Unsupported file type (%s) uploaded.", typ)) } // Generate filename fName := generateFileName(file.Filename) // Read file contents in memory src, err := file.Open() if err != nil { return echo.NewHTTPError(http.StatusBadRequest, fmt.Sprintf("Error reading file: %s", err)) } defer src.Close() // Upload the file. fName, err = app.media.Put(fName, typ, src) if err != nil { app.log.Printf("error uploading file: %v", err) cleanUp = true return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error uploading file: %s", err)) } defer func() { // If any of the subroutines in this function fail, // the uploaded image should be removed. if cleanUp { app.media.Delete(fName) app.media.Delete(thumbPrefix + fName) } }() // Create thumbnail from file. thumbFile, err := createThumbnail(file) if err != nil { cleanUp = true app.log.Printf("error resizing image: %v", err) return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error resizing image: %s", err)) } // Upload thumbnail. thumbfName, err := app.media.Put(thumbPrefix+fName, typ, thumbFile) if err != nil { cleanUp = true app.log.Printf("error saving thumbnail: %v", err) return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error saving thumbnail: %s", err)) } uu, err := uuid.NewV4() if err != nil { app.log.Printf("error generating UUID: %v", err) return echo.NewHTTPError(http.StatusInternalServerError, "Error generating UUID") } // Write to the DB. if _, err := app.queries.InsertMedia.Exec(uu, fName, thumbfName, 0, 0); err != nil { cleanUp = true app.log.Printf("error inserting uploaded file to db: %v", err) return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error saving uploaded file to db: %s", pqErrMsg(err))) } return c.JSON(http.StatusOK, okResp{true}) } // handleGetMedia handles retrieval of uploaded media. func handleGetMedia(c echo.Context) error { var ( app = c.Get("app").(*App) out []media.Media ) if err := app.queries.GetMedia.Select(&out); err != nil { return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error fetching media list: %s", pqErrMsg(err))) } for i := 0; i < len(out); i++ { out[i].URI = app.media.Get(out[i].Filename) out[i].ThumbURI = app.media.Get(thumbPrefix + out[i].Filename) } return c.JSON(http.StatusOK, okResp{out}) } // deleteMedia handles deletion of uploaded media. func handleDeleteMedia(c echo.Context) error { var ( app = c.Get("app").(*App) id, _ = strconv.Atoi(c.Param("id")) ) if id < 1 { return echo.NewHTTPError(http.StatusBadRequest, "Invalid ID.") } var m media.Media if err := app.queries.DeleteMedia.Get(&m, id); err != nil { return echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error deleting media: %s", pqErrMsg(err))) } app.media.Delete(m.Filename) app.media.Delete(thumbPrefix + m.Filename) return c.JSON(http.StatusOK, okResp{true}) } // createThumbnail reads the file object and returns a smaller image func createThumbnail(file *multipart.FileHeader) (*bytes.Reader, error) { src, err := file.Open() if err != nil { return nil, err } defer src.Close() img, err := imaging.Decode(src) if err != nil { return nil, echo.NewHTTPError(http.StatusInternalServerError, fmt.Sprintf("Error decoding image: %v", err)) } // Encode the image into a byte slice as PNG. var ( thumb = imaging.Resize(img, thumbnailSize, 0, imaging.Lanczos) out bytes.Buffer ) if err := imaging.Encode(&out, thumb, imaging.PNG); err != nil { return nil, err } return bytes.NewReader(out.Bytes()), nil }